Varnish applicator for electric motor

ABSTRACT

A varnish injection system includes a varnish injector including a base, a nozzle extending from the base, and a spacer disposed on the nozzle, and an electric motor including a stator, a wire, and an insulating layer between the stator and the wire. The nozzle is arranged to deposit varnish between the stator and the insulating layer. The nozzle and the stator define a gap therebetween when the spacer engages the stator.

FIELD

The present disclosure relates to electric motors, and more particularlyto maintenance of electric motor components.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Electric propulsion in vehicles provide an alternative to internalcombustion engines. The electric propulsions use electric motors topropel the vehicle. Applying varnish to such motors provides corrosionand contaminant resistance to the motors, increasing an operationlifetime of the electric propulsion. The varnish can be applied with amachine designed to apply the varnish to the various components of themotors.

The present disclosure addresses challenges related to varnishapplication to electric motors.

SUMMARY

This section provides a general summary of the disclosure and is not acomprehensive disclosure of its full scope or all of its features.

In one form, a varnish injection system includes a varnish injectorincluding a base, a nozzle extending from the base, and a spacerdisposed on the nozzle, and an electric motor including a stator, awire, and an insulating layer between the stator and the wire. Thenozzle is arranged to deposit varnish between the stator and theinsulating layer. The nozzle and the stator define a gap therebetweenwhen the spacer engages the stator.

In variations of the system of the above paragraph, which may beimplemented individually or in any combination: the nozzle is furtherarranged to deposit varnish and between the insulating layer and thewire; the varnish injector further includes a spring urging the nozzletoward the base; the spacer engages the stator upon urging of the nozzleby the spring toward the base; the insulating layer is paper; the spaceris a ring having an inner diameter sized to frictionally fit about thenozzle; the spacer has an outer diameter sized to define the gap betweenthe nozzle and the stator; the stator includes a pair of fingersdefining a slot, and the wire is disposed in the slot; the spacer is aflexible material; the electric motor includes a plurality of wiresradially spaced from each other, and the electric motor is rotatable tomove each of the plurality of wires toward the nozzle; the spacersubstantially maintains the gap when the electric motor is rotated; theelectric motor includes a first wire and a second wire, and the electricmotor is rotatable to move the first wire away from the nozzle and tomove the second wire toward the nozzle.

In another form of the present disclosure, a method for applying varnishto an electric motor includes rotating the electric motor, urging aspacer against an outer surface of the electric motor, and actuating anozzle disposed in the spacer to deposit varnish onto the electric motorthrough a gap between the nozzle and the electric motor.

In variations of the method of the above paragraph: the method furtherincludes depositing the varnish between a stator of the electric motorand an insulating layer of the electric motor; depositing the varnishbetween an insulating layer of the electric motor and a wire of theelectric motor; rotating the electric motor at a constant speed; movinga base in a radial direction of the electric motor to urge the spaceragainst the outer surface of the electric motor; the electric motorincludes a stator and a wire, the stator includes a slot, the wire isdisposed in the slot, and the method further comprises depositing thevarnish into the slot between the stator and the wire.

In another form of the present disclosure, a system includes an electricmotor including a stator, a wire, and an insulating layer disposedbetween the stator and the wire, the stator including a slot, and avarnish injector including a base, a nozzle extending from the base, aspring urging the nozzle toward the base, and a spacer disposed aroundthe nozzle. The wire and the insulating layer are disposed in the slotof the stator. The nozzle and the stator define a gap therebetween whenthe spacer engages the stator upon urging by the spring and the nozzleis arranged to deposit varnish into the gap, the varnish flowing to afirst space defined between the stator and the insulating layer and to asecond space defined between the insulating layer and the wire.

In variations of the system of the above paragraph: the spacer engagesan outer surface of the stator to define the gap.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

In order that the disclosure may be well understood, there will now bedescribed various forms thereof, given by way of example, referencebeing made to the accompanying drawings, in which:

FIG. 1 is a perspective view of a stator of an electric motor;

FIG. 2 is a cross-sectional view of the electric motor;

FIG. 3A is a cross-sectional view a varnish injection system;

FIG. 3B is a detailed view of a pair of laminates of the stator shown inFIG. 3A;

FIG. 4 is a side view of another varnish injection system including aspacer;

FIG. 5 is a perspective view of a rotatable mount that moves theelectric motor;

FIG. 6 is a perspective view of another varnish injection systemapplying varnish to a rotated electric motor;

FIG. 7A is a cross-sectional view of the electric motor including theplurality of wires disposed in a slot;

FIG. 7B is a cross-sectional view of the insulating layer and theplurality of wires contacting walls of the slot;

FIG. 8A is a view of a distal end of one of the laminates of the stator;

FIG. 8B is a view of a distal end of one of the laminates with achamfered edge;

FIG. 8C is a view of the stator with the laminates of FIGS. 8A-8B;

FIG. 9A is a view of the stator with the insulating layer and theplurality of wires disposed in the slot;

FIG. 9B is a cross-sectional view of the slot with injected varnish;

FIG. 10A is a view of the insulating layer;

FIG. 10B is a cross sectional view of the slot with injected varnish;

FIG. 11A is a side view of the electric motor with a clamp;

FIG. 11B is an end view of a first end plate of the clamp;

FIG. 11C is an end view of a second end plate of the clamp; and

FIG. 11D is an end view of the electric motor and the clamp.

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

With reference to FIGS. 1-3B, an electric motor 10 includes a stator 12,a plurality of wires 14, and an insulating layer 16 between the stator12 and the wires 14. The electric motor 10 is a component of an electricpropulsion for a motor vehicle, i.e., an “electric vehicle.” Theelectric motor 10 propels the motor vehicle by rotating one or morewheels of the motor vehicle. In one example, the electric motor 10 is asole propulsion of the vehicle, e.g., in a fully electric vehicle.Alternatively, the electric motor 10 can be part of a hybrid propulsionthat includes an internal combustion engine, e.g., in a hybrid-electricvehicle.

The electric motor 10 includes the stator 12. The stator 12 is astationary component of the electric motor 10 that provides a magneticfield by which a rotor (not shown) rotates. The stator 12 maintainsalignment of the magnetic field to rotate the rotor. The stator 12includes a plurality of laminates 18, i.e., sheets of material fusedtogether. Each laminate 18 is an annular sheet of metal with acontinuous outer edge 20 defining an outer diameter and a plurality offingers 22 extending toward a center point of the annular sheet. Distalends 24 of the fingers 22 define an inner diameter of the laminate 18.Each pair of adjacent fingers 22 of one of the laminates 18 defines aslot 26 therebetween. The slots 26 extend radially from the innerdiameter to an intermediate diameter. The laminates 18 are fused at theouter diameter by, e.g., a weld, and the laminates 18 are free at theintermediate diameter and the inner diameter. Each pair of adjacentlaminates 18 defines a space 28 there between, as shown in FIG. 3B.

With reference to FIGS. 2-3A, the electric motor 10 includes theplurality of wires 14. The wires 14 are an electrically conductingmaterial, e.g., copper. The wires 14 provide electricity to generate themagnetic field that drives the rotor. The wires 14 are disposed in theslots 26 and extend along the stator 12. The wires 14 are disposed fromthe intermediate diameter to the inner diameter in the slots 26 definedby the fingers 22 of the laminates 18.

The electric motor 10 includes the insulating layer 16. The insulatinglayer 16 reduces or prevents electric conduction between the wires 14and the stator 12, preventing interference with the magnetic field torotate the rotor. The insulating layer 16 is, e.g., a paper layer thatis electrically insulative. Each slot 26 of the stator 12 includes aninsulating layer 16 disposed therein between respective wires 14 in theslot 26 and the stator 12.

With reference to FIG. 3A, a varnish injection system 30 providesvarnish 32 to the stator 12, the insulating layer 16, and the wires 14.The varnish 32 protects the stator 12, the insulating layer 16, and thewires 14 from contaminants and corrosive materials that may affectoperation of the electric motor 10. The varnish injection system 30includes a nozzle 34 that provides the varnish 32. The varnish 32 movesvia capillary action into a first gap 36 defined by the stator 12 andthe insulating layer 16 and into a second gap 38 defined by theinsulating layer 16 and the wires 14. The first and second gaps 36, 38extend from a first laminate 40 at a first end 42 of the stator 12 to alast laminate 44 at a second end 46 of the stator 12. That is, thelaminates 18 of the stator include a pair of laminates that define theouter surface of the stator. One of the pair is a “first” laminate 40,and the other of the pair is a “last” laminate 44.

The laminates 18 are stacked along a rotational axis R, and the gaps 36,38 extend along each of the laminates 18 in the rotational axis Rdirection. By capillary action, the varnish 32 flows along the first andsecond gaps 36, 38 and into the spaces 28 between the laminates 18.However, the varnish 32 is typically more beneficial in the first andsecond gaps 36, 38, and less beneficial in the spaces 28 between thelaminates 18. Thus, as described below, reducing the spaces 28 betweenthe laminates 18 reduces a total amount of varnish 32 used and improvescapillary action of the varnish 32 through the stator 12.

The laminates 18 may have uneven outer surfaces 48, and when thelaminates 18 are stacked into the stator 12, the outer surface 48 of thestator 12 may have deviations from the stacking tolerances of theseuneven outer surfaces 48. The uneven outer surface 48 of the stator 12may interfere with deposition of the varnish 32, e.g., by contacting thenozzle 34 or disrupting a stream of varnish 32 entering the slots 26. Todeposit varnish 32 without interference from the stator 12, the nozzle34 can be spaced to a specified gap from the outer surface 48 of thestator 12. The gap can be a specified distance that will prevent theouter surface 48 of the stator 12 from interfering with the nozzle 34,e.g., 2 mm.

With reference to FIG. 4 , a varnish injection system 50 includes avarnish injector 52, the varnish injector 52 including a base 54, anozzle 34 extending from the base 54, and a spacer 56 disposed on thenozzle 34. The varnish injection system 50 of FIG. 4 provides varnish 32to the electric motor 10 without interference from an uneven surface 48of the stator 12, directing varnish 32 to the first and second gaps 36,38 and reducing total varnish consumption during application.

The varnish injector 52 includes the base 54 and the nozzle 34 extendingfrom the base 54. The base 54 is a structure that supports the nozzle 34while the nozzle 34 deposits varnish 32 onto the electric motor 10. Thenozzle 34 is arranged to deposit varnish 32 between the stator 12 andthe insulating layer 16, and further arranged to deposit varnish 32between the insulating layer 16 and the wires 14. The nozzle 34 extendsdownward toward the electric motor 10 to deposit the varnish 32.

The varnish injector 52 includes the spacer 56. The spacer 56 engagesthe outer surface 48 of the stator 12 to space the nozzle 34 from thestator 12. The spacer 56 prevents the nozzle 34 from moving toward thestator 12, defining a gap 58 between the nozzle 34 and the stator 12. Asthe uneven surface 48 of the stator 12 changes, the spacer 56 moves thenozzle 34 away from the stator 12 along the uneven deviations, allowingthe nozzle 34 to deposit varnish 32 into the gap 58 and onto the stator12. The spacer 56 is a ring fixed around the nozzle 34. The ring has aninner diameter sized to frictionally fit about the nozzle 34 and anouter diameter sized to define the gap 58. The spacer 56 is a flexiblematerial, e.g., a polymer.

The varnish injector 52 includes a spring 60. To force the spacer 56 toengage the stator 12, the spring 60 provides an urging force that urgesthe spacer 56 toward the base 54 and onto the outer surface 48 of thestator 12. The spacer 56 engages the stator 12, generating tension inthe spring 60. As the uneven surface 48 of the stator 12 changes, thespring 60 maintains its urging force, forcing the spacer 56 against thesurface 48 of the stator 12 to position the nozzle 34 to deposit varnish32 into the gap 58 between the nozzle 34 and the stator 12. In anotherform, the spring 60 urges the laminates 18 against each other, reducingspaces 28 between the laminates 18 and reducing capillary action ofvarnish 32 into the spaces 28. That is, the tension in the spring 60 istuned to compress the laminates 18 together. In yet another form, asecond varnish injection system (not shown) with a second springcompresses the opposing end of the stator 12, each spring providingtension to compress the laminates 18 and reduce the spaces 28therebetween, reducing capillary action of the varnish 32 between thelaminates 18.

As described above, the stator 12 includes a plurality of fingers 22,each pair of fingers 22 defining a slot 26 therebetween, and the wires14 are radially spaced from each other in the slots 26. The electricmotor 10 is rotatable about the rotational axis R to move each of theplurality of wires 14 toward the nozzle 34. The electric motor 10rotates while the nozzle 34 applies varnish 32, and the spacer 56substantially maintains the gap 58 when the electric motor 10 is rotatedso that the varnish 32 is applied to all of the wires 14 of the electricmotor 10. Specifically, the electric motor 10 is rotatable to move afirst wire 14 away from the nozzle 34 and to move a second wire 14toward the nozzle 34 so that the nozzle 34 can apply varnish 32 to thesecond wire 14 as the first wire 14 moves away from the nozzle 34. Thus,upon a complete rotation of the electric motor 10, the nozzle 34 appliesvarnish 32 to all of the slots 26 of the stator 12 and the wires 14therein.

To apply the varnish 32 to the electric motor 10, the electric motor 10is rotated until an angular position of the electric motor 10 is withina threshold of a specified angular position, the specified angularposition determined to align the nozzle 34 with one of the wires 14disposed in one of the slots 26. The base 54 is moved in a radialdirection of the electric motor 10 to urge the spacer 56 against theouter surface 48 of the stator 12. The nozzle 34 is actuated to depositvarnish 32 through the gap 58 and into the slot 26 and the gaps 36, 38therein.

With reference to FIGS. 5-6 , another embodiment of the varnishinjection system 62 includes a rotatable mount 64 that rotates theelectric motor 10. The rotatable mount 64 supports the electric motor 10and is movable about three axes of rotation. For example, the rotatablemount 64 includes a universal joint 66 and an arm 68 that connects theuniversal joint 66 and the electric motor 10. In another example notshown in the FIGS., the rotatable mount 64 includes a set of bevel gearsto rotate the electric motor 10.

The electric motor 10 defines a rotational axis R about which the stator12 rotates and a radial axis A along a radius of the stator 12. Theuniversal joint 66 rotates the arm 68 and the electric motor 10 relativeto a vertical axis B, i.e., an axis aligned with the direction ofgravity, g. When the electric motor 10 is in a neutral position, therotational axis R is perpendicular to the vertical axis B and the radialaxis A is aligned with the vertical axis B. The rotatable mount 64rotates the electric motor 10 about the rotational axis R to define anangle θ between radial axis A and the vertical axis B. When the electricmotor 10 is rotated to define a nonzero angle θ between the radial axisA and the vertical axis B, varnish 32 flows with the assistance ofgravity into the gaps 36, 38 defined between the stator 12, the wires14, and the insulating layer 16.

The varnish injection system 62 of FIGS. 5-6 includes a varnishinjector. The varnish injector 70 includes a base 72 and a nozzle 34extending from the base 72. The nozzle 34 extends along the verticalaxis B aligned with the direction of gravity, g. The nozzle 34 isarranged to deposit varnish 32 into the gaps 36, 38 defined between thestator 12 and the wire 14 when the rotatable mount 64 rotates theelectric motor 10 to the nonzero angle θ, as shown in FIG. 6 . Thenozzle 34 deposits varnish 32 with the assistance of gravity, and thevarnish 32 flows into the gaps 36, 38 via gravity and capillary action.When the electric motor 10 is rotated to the nonzero angle θ relative tothe vertical axis B, the insulating layer 16 extends toward the nozzle34 from the stator 12 and the wire 14 extends toward the nozzle 34 fromthe insulating layer 16.

The rotatable mount 64 rotates the electric motor 10 about therotational axis R, and the varnish injection system 62 applies varnish32 to the electric motor 10 as the electric motor 10 rotates. Theelectric motor 10 is rotatable to a specified angle 4) about therotational axis R to align each slot 26 with the nozzle 34 of thevarnish injector 70. The specified angle 4) is based on the number ofslots 26 in the stator 12, the slots 26 being arranged substantiallyevenly about the stator 12. Each slot 26 is assigned a specified angle4) relative to a neutral position, and the rotatable mount 64 isarranged to rotate the electric motor 10 to the specified angle 4) toalign the respective slot 26 with the nozzle 34 to receive varnish 32.The rotatable mount 64 rotates the electric motor 10 to align a firstslot 26 with the nozzle 34, and then rotates the electric motor 10 toalign a next slot 26 upon deposition of varnish 32 to the first slot 26,and continues to rotate the electric motor 10 until each slot 26 hasbeen aligned with the nozzle 34 to receive varnish 32. Thus, therotatable mount 64 provides varnish 32 to each slot 26, each wire 14within each slot 26, and to each insulating layer 16 in each slot 26.

To apply the varnish 32, the electric motor 10 is rotated to thespecified nonzero angle θ between the radial axis A and the verticalaxis B. The varnish injector 70 including the nozzle 34 extending alongthe vertical axis B is actuated to deposit varnish 32 into the slots 26.The electric motor 10 is rotated about the rotational axis R to applythe deposited varnish 32 onto each of the wires 14 disposedcircumferentially around the stator 12. The varnish 32 is deposited intothe gaps 36, 38 of each slot 26. The varnish injector 70 is deactivatedupon completion of a full rotation of the electric motor 10 about therotational axis R.

With reference to FIGS. 7A-10B, the plurality of laminates 18 arestacked along the rotational axis R and fused to form the stator 12. Thecircular laminates 18 include a plurality of fingers 22, each finger 22having a distal end 24 extending toward a center point of the laminate18. The fingers 22 define slots 26 therebetween, as described above,each slot 26 including a first wall 74, a second wall 76, and a floor 78extending from the first wall 74 to the second wall 76.

When the insulating layer 16 is disposed in the slot 26, the insulatinglayer 16 may block varnish 32 from flowing to the walls 74, 76 and thefloor 78 of the slot 26. The rigidity of the paper of the insulatinglayer 16 and/or static forces can press the paper against the fingers 22defining the slot 26, blocking the varnish 32 as shown in FIGS. 7A-7B.Thus, as shown in FIGS. 8A-10B, the laminates 18 and/or the insulatinglayer 16 can be modified to allow varnish 32 to flow onto the walls 74,76 and the floor 78 of the slot 26.

With reference to FIGS. 8A-8C, three fingers 80, 82, 84 of threerespective laminates 18 define a space 86 therebetween through whichvarnish 32 flows. FIG. 8A shows a distal end 24 of the first finger 80and the third finger 84, and FIG. 8B shows a distal end 24 of the secondfinger 82. The distal end 24 of the second finger 82 has a chamferededge 88, as shown in FIG. 8B. When the first, second, and third fingers80, 82, 84 are stacked in the stator 12, as shown in FIG. 8C, thechamfered edge 88 of the second finger 82 forms the space 86 between thefirst and third fingers 80, 84. Each respective finger 80 of a firstlaminate 18 thus defines the space 86 with an adjacent finger 82 of asecond laminate 18 and a subsequent finger 84 of a third laminate 18.

With reference to FIGS. 9A-9B, the space 86 between the first, second,and third fingers 80, 82, 84 allows varnish 32 to flow along the walls74, 76 of the slot 26. The distal end 24 of the second finger 82 withthe chamfered edge 88 is spaced from the insulating layer 16, andvarnish 32 can flow through the space 86 into a gap 90 between theinsulating layer 16 and the wall 74 and into the second gap 92 betweenthe insulating layer 16 and the second wall 76. The electric motor 10includes a plurality of insulating layers 16, each insulating layer 16disposed in one of the slots 26 and extending between the respectivewalls 74, 76 defining the one of the slots 26, and the spaces 86 formedbetween each insulating layer 16 and each chamfered edge 88 allowvarnish 32 to flow into each of the gaps 90, 92 between the insulatinglayer 16 and the walls 74, 76 of the slot 26.

Alternatively, as shown in FIGS. 10A-10B, the insulating layer 94 caninclude spaces 96 through which varnish 32 flows. In the example of FIG.10A, the insulating layer 94 is a sheet that includes a top portion 98and a plurality of fingers 100 extending from the top portion 98. Thefingers 100 define respective spaces 96 therebetween adjacent fingers100. The insulating layer 94 extends along a distal end of the firstwall 74. The insulating layer 94 includes a second top portion 102extending along the distal end of the second wall 76 of the slot 26. Thesecond top portion 102 including a plurality of second fingers 104defining respective second spaces 106 therebetween adjacent secondfingers 104. The first and second fingers 100, 104 extend toward thecenter point of the stator 12. Thus, the insulating layer 94 definesgaps 90, 92 with the first and second walls 74, 76 that include thespaces 96 and the second spaces 106 defined by the fingers 100 and thesecond fingers 104, and, as shown in FIG. 10B, varnish 32 flows throughthe spaces 96 and the second spaces 106 and into the gaps 90, 92.

To apply the varnish 32, a varnish injector (such as one of the varnishinjectors 52, 70 described above) is positioned above a gap 90, 92between the insulating layer 94 and the adjacent wall 74, 76 of thestator 12. The gap 90, 92 is defined by a portion of the insulatinglayer 94 that is spaced from a portion of the adjacent wall 74, 76 ofthe stator 12. The varnish injector injects varnish 32 into the gap 90,92 to the floor 78 between the walls 74, 76 and the insulating layer 94.

With reference to FIGS. 11A-11D, a clamp 108 is attached to the electricmotor 10. The laminates 18 of the stator 12 define spaces 28therebetween at the distal ends 24 of the fingers 22, and the clamp 108compresses the laminates 18 to close the spaces 28, reducing movement ofvarnish 32 into the spaces 28. By closing the spaces 28 upon engagementwith the electric motor, a varnish injector (such as the injectors 52,70 described above) applies varnish 32 to the electric motor 10 withless varnish 32 entering into the spaces 28 where the varnish 32 may notbe needed, and the capillary action of the varnish 32 through the slot26 is improved.

Referring to FIG. 11A, the clamp 108 includes a beam 110, a first endplate 112, and a second end plate 114. The beam 110 is a substantiallystraight member extendable along the rotational axis R of the electricmotor 10. The first end plate 112 fixed to the beam 110 and engageableto the first end 42 of the stator 12. The second end plate 114 isreleasably connected the beam 110 and engageable to the second end 46 ofthe stator 12. To attach the clamp 108 to the electric motor 10, thebeam 110 is inserted into the electric motor 10 until the first endplate 112 engages the first end 42, and then the second end plate 114 isattached to the beam 110 at the second end 46. The beam 110 pulls thefirst end plate 112 toward the second end plate 114, compressing thelaminates 18 of the stator 12 therebetween.

The first end plate 112 is engageable to the first laminate 40 of thestator 12. The second end plate 114 is engageable to the last laminate44 of the stator 12. The first end plate 112 compresses respectivedistal ends 24 of the fingers 22 of the first laminate 40, and thesecond end plate 114 compresses respective distal ends 24 of the fingers22 of the last laminate 44. The slots 26 of the stator 12 are disposedradially outward from a location at which the end plates 112, 114 engagethe stator 12. By engaging the distal ends 24 of the fingers 22, thefirst and second end plates 112, 114 compress the laminates 18 atlocations where the laminates 18 are elastically deformable, reducingthe spaces 28 between the laminates 18 while leaving the slots 26 opento receive varnish 32.

The clamp 108 includes a fastener 116. The fastener 116 connects thesecond end plate 114 to the beam 110. The fastener 116 in the example ofFIGS. 11A, 11C is a screw. The screw includes threads 118 that engagethreads 120 of the beam 110, moving the screw into the beam 110. As thescrew moves into the beam 110, the second end plate 114 moves toward thefirst end plate 112, compressing the laminates 18 of the stator 12therebetween.

With reference to FIGS. 11B, 11D, the first end plate 112 includes arigid inner portion 122 and a flexible annular portion 124. The flexibleannular portion 124 extends from the rigid inner portion 122 to theelectric motor 10. The flexible annular portion 124 includes an outeredge 126 that engages the stator 12. The second end plate 114 includes arigid inner portion 128 and a flexible annular portion 130 including anouter edge 132 that engages the stator 12. Alternatively, the first andsecond end plates 112, 114 are entirely rigid, entirely flexible, oranother combination of a rigid material and a flexible material.

A varnish injector deposits varnish 32 to the electric motor 10 when theclamp 108 engages the electric motor 10. The varnish injector isarranged to inject varnish 32 along the slots 26 defined by thecompressed laminates 18. As described above, the varnish injector isarranged to inject the varnish 32 into the gap 36 between the stator 12and the insulating layer 16 disposed in the slot 26 and into the gap 38between the insulating layer 16 and the wire 14. The compressedlaminates 18 improve capillary action in the gap 36 between the stator12 and the insulating layer 16 because there are fewer spaces 28 todecrease surface tension of the flowing varnish 32.

To apply the varnish 32, the beam 110 is inserted through the cavity ofthe electric motor 10 to apply the first end plate 112 to the first end42 of the stator 12. The second end plate 114 is applied to the secondend 46 of the stator 12 and secured to the beam 110 with the removablefastener 116. The first and second end plates 112, 114 compress thestator 12 therebetween upon rotation of the removable fastener 116 intothe beam 110, moving the first end plate 112 toward the second end plate114. A varnish injector applies the varnish 32 to the slot 26 until thevarnish 32 reaches the second end 46 of the stator 12.

Unless otherwise expressly indicated herein, all numerical valuesindicating mechanical/thermal properties, compositional percentages,dimensions and/or tolerances, or other characteristics are to beunderstood as modified by the word “about” or “approximately” indescribing the scope of the present disclosure. This modification isdesired for various reasons including industrial practice, material,manufacturing, and assembly tolerances, and testing capability.

As used herein, the phrase at least one of A, B, and C should beconstrued to mean a logical (A OR B OR C), using a non-exclusive logicalOR, and should not be construed to mean “at least one of A, at least oneof B, and at least one of C.”

The apparatuses and methods described in this application may bepartially or fully implemented by a special purpose computer created byconfiguring a general-purpose computer to execute one or more particularfunctions embodied in computer programs. The functional blocks,flowchart components, and other elements described above serve assoftware specifications, which can be translated into the computerprograms by the routine work of a skilled technician or programmer.

The description of the disclosure is merely exemplary in nature and,thus, variations that do not depart from the substance of the disclosureare intended to be within the scope of the disclosure. Such variationsare not to be regarded as a departure from the spirit and scope of thedisclosure.

What is claimed is:
 1. A varnish injection system comprising: a varnishinjector including a base, a nozzle extending from the base, and aspacer disposed on the nozzle; and an electric motor including a stator,a wire, and an insulating layer between the stator and the wire, whereinthe nozzle is arranged to deposit varnish between the stator and theinsulating layer, and wherein the nozzle and the stator define a gaptherebetween when the spacer engages the stator.
 2. The varnishinjection system according to claim 1, wherein the nozzle is furtherarranged to deposit varnish between the insulating layer and the wire.3. The varnish injection system according to claim 1, wherein thevarnish injector further includes a spring urging the nozzle toward thebase.
 4. The varnish injection system according to claim 3, wherein thespacer engages the stator upon urging of the nozzle by the spring towardthe base.
 5. The varnish injection system according to claim 1, whereinthe insulating layer is paper.
 6. The varnish injection system accordingto claim 1, wherein the spacer is a ring having an inner diameter sizedto frictionally fit about the nozzle.
 7. The varnish injection systemaccording to claim 6, wherein the spacer has an outer diameter sized todefine the gap between the nozzle and the stator.
 8. The varnishinjection system according to claim 1, wherein the stator includes apair of fingers defining a slot, and the wire is disposed in the slot.9. The varnish injection system according to claim 1, wherein the spaceris a flexible material.
 10. The varnish injection system according toclaim 1, wherein the electric motor includes a plurality of wiresradially spaced from each other, and the electric motor is rotatable tomove each of the plurality of wires toward the nozzle.
 11. The varnishinjection system according to claim 10, wherein the spacer substantiallymaintains the gap when the electric motor is rotated.
 12. The varnishinjection system according to claim 10, wherein the electric motorincludes a first wire and a second wire, and the electric motor isrotatable to move the first wire away from the nozzle and to move thesecond wire toward the nozzle.
 13. A method for applying varnish to anelectric motor, the method comprising: rotating the electric motor;urging a spacer against an outer surface of the electric motor; andactuating a nozzle disposed in the spacer to deposit varnish onto theelectric motor through a gap between the nozzle and the electric motor.14. The method according to claim 13, further comprising depositing thevarnish between a stator of the electric motor and an insulating layerof the electric motor.
 15. The method according to claim 13, furthercomprising depositing the varnish between an insulating layer of theelectric motor and a wire of the electric motor.
 16. The methodaccording to claim 13, further comprising rotating the electric motor ata constant speed.
 17. The method according to claim 13, furthercomprising moving a base in a radial direction of the electric motor tourge the spacer against the outer surface of the electric motor.
 18. Themethod according to claim 13, wherein the electric motor includes astator and a wire, the stator includes a slot, the wire is disposed inthe slot, and the method further comprises depositing the varnish intothe slot between the stator and the wire.
 19. A system comprising: anelectric motor including a stator, a wire, and an insulating layerdisposed between the stator and the wire, the stator including a slot;and a varnish injector including a base, a nozzle extending from thebase, a spring urging the nozzle toward the base, and a spacer disposedaround the nozzle, wherein the wire and the insulating layer aredisposed in the slot of the stator, and wherein the nozzle and thestator define a gap therebetween when the spacer engages the stator uponurging by the spring and the nozzle is arranged to deposit varnish intothe gap, the varnish flowing to a first space defined between the statorand the insulating layer and to a second space defined between theinsulating layer and the wire.
 20. The system according to claim 19,wherein the spacer engages an outer surface of the stator to define thegap.